C#结合OpenCVSharp4使用直方图算法实现图片相似度比较

        /// <summary>
        /// 直方图相关性 
        /// 结果越接近1 则越相似
        /// 图片相似度识别（精度不高，速度较快，可用于以图搜图）
        /// </summary>
        /// <param name="imgFile1"></param>
        /// <param name="imgFile2"></param>
        public double Compare_Hist(string imgFile1, string imgFile2)
        {
            var matA = Cv2.ImRead(imgFile1);
            var matB = Cv2.ImRead(imgFile2);
            // 拆分通道
            Cv2.Split(matA, out Mat[] matA_S);
            Cv2.Split(matB, out Mat[] matB_S);
            //直方图的像素范围   
            Rangef[] histRange = { new Rangef(0, 256) };
            //直方图数组大小
            int[] histSize = { 256 };
            //直方图输出数组
            Mat hist_A = new Mat();
            Mat hist_B = new Mat();
            bool uniform = true, accumulate = false;
            Cv2.CalcHist(matA_S, new int[] { 0, 1, 2 }, null, hist_A, 1, histSize, histRange, uniform, accumulate);
            Cv2.CalcHist(matB_S, new int[] { 0, 1, 2 }, null, hist_B, 1, histSize, histRange, uniform, accumulate);
            //归一化，排除图像分辨率不一致的影响
            Cv2.Normalize(hist_A, hist_A, 0, 1, NormTypes.MinMax, -1, null);
            Cv2.Normalize(hist_B, hist_B, 0, 1, NormTypes.MinMax, -1, null);
            //相关性比较
            var res = Cv2.CompareHist(hist_A, hist_B, HistCompMethods.Correl);
            return res;
        }